The effect of initiation of child supplementation on resumption of post-partum menstruation

The effects of initiation of solid and liquid supplementation on resumption of post-partum menstruation are examined, using data from a 2-year prospective study of birth interval dynamics from central Java, Indonesia. The sample analysed consisted of 444 women who experienced resumption of menses while breast-feeding, women who were breast-feeding and amenorrhoeic at the end of the study, or women who resumed menstruation or were censored after infant mortality and weaning which preceded the resumption of menses. Multivariate hazard model analysis was used to assess the significance of supplementation, various breast-feeding covariates, and age and parity of the dependent variable. Because the timing of supplementation varies, the supplementation variables were introduced into the analysis as time-varying covariates. For the mothers in the sample, solid and liquid supplementation was initiated at medians of 2.1 and 8.0 months respectively. The former had a significant effect on resumption of menses, while the latter was only marginally significant. Earlier supplementation meant shorter durations of amenorrhoea for the majority of women. However, the effect was not consistent across all categories of women. For the small group of mothers who were low intensity breast-feeders (less than or equal to 6 minutes per nursing episode) or as low frequency day-time breast-feeders (less than or equal to 6 nursing episodes per day-time), earlier supplementation had no additional effect on their rate of resumption of menses post-partum.     

A hazards model analysis of breastfeeding variables and maternal age on return to menses postpartum in rural Indonesian women

There is mounting research evidence that the duration of lactational amenorrhea is dependent on the infant's suckling input. Multivariate techniques, including the proportional hazards model, offer an effective methodological approach for sorting through the variables that contribute to a process as complex as breastfeeding. This approach was utilized on a sample of 382 mothers who participated in the Ngaglik Study, a longitudinal investigation of maternal health and nutrition, infant development, child spacing, and fertility trends in Central Java, Indonesia. 3 primary breastfeeding variables--average number of nursing episodes during the day, average number of nursing episodes during the night, and average minutes per episode--were obtained from monthly interviews with study subjects, 260 of whom experienced return to menses while breastfeeding. The mean and median durations of amenorrhea were 17.3 and 16.4 months, respectively. The reported total number of suckling bouts per 24 hours averaged 8.85, with an average of 8.23 minutes per nursing episode. Amenorrhea duration ranged from 19.2 months in mothers who nursed 6 or more times during the day-time hours to 12.2 months in mothers who nursed an average of 6 minutes or less per episode. The variable of minutes per nursing bout has the greatest effect on return to menses, while the average number of day-time feeds has the least; the number of night-time feeds is intermediate. When age was introduced into the model, the effects of the nursing variables on return of menses remained constant relative to 1 another but the increment in the risk of menstruating increased with younger age. In summary, this analysis indicates that low intensity breastfeeding with 3 or fewer episodes reported at night, 6 or fewer episodes reported for the day, 6 or less minutes reported per nursing episode, and younger age all increase the risk of early postpartum resumption of menses.     

A biobehavioral model for breastfeeding effects on return to menses postpartum in Javanese women

Abstract

This paper examines the effects of nursing behavior on the duration of lactation amenorrhea in 382 rural Indonesian women who experienced resumption of menses while breastfeeding or were breastfeeding and amenorrheic at the end of a two‐year prospective study. Three primary breastfeeding variables (number of night‐time nursing bouts, number of day‐time nursing bouts, and minutes per bout) were used to develop a behavioral model for breastfeeding. Four breastfeeding patterns were identified for these women. These were designated as: (1) low intensity, (2) medium‐low intensity, (3) medium‐high intensity, and (4) high intensity breastfeeding behavior. Menses resumed at medians of 11.2,16.0,17.6, and 20.8 months, respectively, for these groups. The relationships among the breastfeeding variables in the behavioral model and return to menses were developed and tested by life table and proportional hazards models. Ten per cent of the high intensity breastfeeding group (6 women) delayed menses between 33 and 52 weeks, while 90 per cent (56 women) postponed return of menses for over one year.     

Nursing behaviour and its relation to duration of post-partum amenorrhoea in an Andean community

Nu?oa is a high altitude rural Peruvian community characterized by socioeconomic stratification and differential access to the market economy. Nursing practices and the effects of nursing are also stratified; this translates into a risk of menses at 12 months post-partum nearly seven times greater in wealthier than in poorer women. Most nursing occurs in the morning, among those who practice on-demand breast-feeding. Nursing episodes are clustered into sessions; the amount of breast-feeding is regulated by varying the number of episodes per session rather than by changing the duration of suckling episodes or the frequency of sessions per hour. Thus, resumption of ovulation is not dependent on the variable spacing of nursing episodes or sessions. The components of nursing activity most likely to be responsible for variation in the duration of post-partum amenorrhoea in these nursing women are mean session duration and mean number of episodes per session. The mean duration of morning nursing sessions is negatively associated with infant's age, reflecting the greater reliance of younger children on breast-milk. The mean duration of afternoon nursing sessions is positively associated with mother's age, independent of infant's age, possibly reflecting maternal age-related variation in milk production capabilities. Baby minding by older daughters may also help to explain variation in afternoon nursing.     

The recovery of fertility during breast-feeding in Assiut, Egypt

A longitudinal study of twenty-six breast-feeding and twelve non-breast-feeding postpartum women was conducted in Assiut, Egypt in order to determine the time that ovulation resumed after childbirth, and the effect of breast-feeding frequency on the period of lactational anovulation. Breast-feeding women experienced the onset of follicular development, vaginal bleeding, ovulation and pregnancy significantly later than women who did not breast-feed. Ovulatory and non-ovulatory breast-feeders reported similar frequencies of breast-feeding episodes. The introduction of dietary supplements commonly preceded ovulation. An algorithm using three simple variables observable to the breast-feeding mother was found to predict up to 100% of the first ovulations. All breast-feeding women who did not give supplements and did not have a vaginal bleeding episode by 6 months postpartum were anovular by strict criteria for ovulation. Ovulation did not precede bleeding or supplementation in the women who experienced these events before 6 months, yielding a highly effective formula for preventing unplanned pregnancy by the informed use of breast-feeding.     

Lactational amenorrhoea in well-nourished Toba women of Formosa, Argentina

The proximate causes of the contraceptive effect of lactation are still a matter of productive debate. This study sought to disentangle the relative impact that intense breast-feeding practices and maternal nutrition have on the regulation of ovarian function in nursing women. A mixed-longitudinal, direct-observational, prospective study was conducted of the return to postpartum fecundity in 113 breast-feeding, well-nourished Toba women. A sub-sample of 70 women provided data on nursing behaviour, daily activities, diet quality and urinary levels of oestrone and progesterone metabolites. Well-nourished, intensively breast-feeding Toba women experienced a relatively short period of lactational amenorrhoea (10.2 +/- 4.3 months) and a high lifetime fertility (TFR=6.7 live births/woman). Duration of lactational amenorrhoea was not correlated with any of the nursing parameters under study or with static measures of maternal nutritional status. The results indicated that the pattern of resumption of postpartum fertility could be explained, at least partly, by differences in individual metabolic budgets. Toba women resumed postpartum ovulation after a period of sustained positive energy balance. As the relative metabolic load hypothesis suggests, the variable effect of lactation on postpartum fertility may not depend on the intensity of nursing per se but rather on the energetic stress that lactation represents for the individual mother.     

Blood velocities to the female breast during lactation and following oxytocin injections

A heterodyne pulsed doppler velocitymeter was used to measure blood velocities in the mammary branch of the lateral thoracic artery during breast-feeding and after oxytocin injections. A few heart beats before the mother felt the milk-ejection reflex, blood velocities fell rapidly by 40-50%, and then increased during the next 1-2 min. Synthetic oxytocin was given intravenously to lactating women, both in doses believed to be physiological in milk-ejection and larger, and the same velocity changes occurred. Synthetic oxytocin was also given to non-lactating women who had never been pregnant or who had breast-fed previously and to one man. In these a rapid increase in velocity was observed after about a half a minute, lasting for 1-2 min. In addition to the short-term effects of breast-feeding, blood velocity increased rapidly towards the end of nursing or a few minutes afterwards, with a maximal increase of 25-50%. It then slowly returned to pre-nursing values during the following 30-60 min. This pattern was seen in both breasts, independent of which breast the infant had been sucking.     

Studies on perceived breast-milk insufficiency: relation to attitude and practice.

Fifty-one mother-infant pairs were followed prospectively by home visits and telephone contacts during the first 6 months post-partum. Comparisons between mothers who experienced lactation crises because of perceived breast-milk insufficiency (crisis group) and those who did not (non-crisis group) revealed differences in attitudes to breast-feeding, breast-feeding behaviour and sexual life. The crisis group tended to initiate breast-feeding for infant-related reasons more frequently than the non-crisis group, which more frequently gave mother-related reasons. During the course of breast-feeding attitude changes in a negative direction were significantly more common in the crisis group. No difference was found between the groups in the resumption of sexual life, but 59% of all the women claimed that they experienced less or no desire compared to before pregnancy and, of these, a significantly higher proportion belonged to the crisis group.     

Nursing practices and lactation amenorrhoea

The purpose of this study is to test the hypothesis that nursing behavior is an independent underlying factor of importance in duration of amenorrhea. Multivariate analysis is applied to information on frequency and duration of nursing practices, maternal age, and nutritional status assessed by weight for height in a sample of 32 middle-class American women with a wide range of nursing behavior. The mothers were followed for 2 years postpartum, data being collected during 8 home visits by interview and by nursing records kept by the mothers. Amenorrhea lasted 1.3 to 27.1 months in the sample as a whole. Those women who nursed frequently (8/day) during exclusive breastfeeding remained amenorrheic longer than infrequent nursers, introduced supplements later, and did not resume menses as promptly thereafter. They continued an hour or more of night nursing during supplemented nursing. Duration of exclusive nursing and night nursing after supplementation were the major influences on duration of amenorrhea. This strong association favors the hypothesis that the underlying factor is nursing behavior. Mother's age, weight-for-height, and nursing frequency before supplementation showed no significant effect. Those women who introduced supplements late and maintained at least an hour of night nursing had a prolonged period of amenorrhea. The median for this group was 6-10 months longer than that for those who started supplements early and/or reduced subsequent night nursing to less than an hour. The recommendation that women must suckle their babies at least 5 times a day with a total suckling duration of more than 65 minutes per day is not sufficient. The findings reported here suggest that if women nurse exclusively for the 1st half year, maintaining night nursing after introducing supplements is important. If they supplement earlier, then they will lose the contraceptive protection of lactation, irrespective of how they nurse.     

Breast-feeding after vertical mammaplasty with medial pedicle

A retrospective study was performed in which the breast-feeding success of women of childbearing age (15 to 40 years) with macromastia but no prior breast surgery was compared with that of women of similar age who had undergone medial pedicle/vertical pattern reduction mammaplasty. All women completed a self-administered questionnaire that provided information on their breast-feeding success. The control group consisted of 149 women with macromastia (mean age, 27 years) who had been evaluated for possible breast reduction surgery and who had children before their consultation. The study group consisted of 58 women (mean age, 29 years) who had children after their vertical mammaplasty. The mean weight of breast tissue removed was 610 g per breast. None of the patients had absent nipple sensation. A period of 2 weeks or more was chosen as the defining duration of a successful breast-feeding attempt. Those individuals judged able to breast-feed were further classified on the basis of having breast-fed exclusively or with supplementation. The results demonstrated that, of the women who attempted to breast-feed, 61 percent in the control group and 65 percent in the study group were successful, with no significant difference between the groups (p > 0.05). The breakdown of the successful groups indicated that 36 percent in the control group and 38 percent in the study group supplemented their breast-feeding with formula. The groups were not significantly different (p > 0.05). In conclusion, this study found no significant difference in the rate of breast-feeding success between women who had medial pedicle/vertical pattern reduction mammaplasty and women who had no prior breast surgery.     

Effect of breast-feeding on pituitary-ovarian function after childbirth

Pituitary and ovarian function at the end of pregnancy and during the first six weeks after delivery was investigated serially in women who fully breast-fed their infants and in women who did not. In the women who did not breast-feed the plasma prolactin level decreased rapidly and from the third day after delivery was significantly lower than in the breast-feeding mothers, reaching the normal range of the menstrual cycle by the third week of the puerperium. In the breast-feeding mothers the plasma prolactin was still raised six weeks after delivery. The levels of FSH in both groups were identical and increased over the third week of the puerperium. Plasma oestrogen fell steeply in both groups during the first two weeks after delivery. In the breast-feeding mothers plasma oestrogen remained depressed but increased in the non-lactating women, reflecting follicular development in the ovary in response to FSH; the plasma oestrogen levels were significantly higher in the non-lactating women from the 17th day of the puerperium onwards. These findings support the concept that in breast-feeding women prolactin delays the return of ovulation by inhibiting the ovarian response to FSH stimulation.     

Brief description of WHO protocol for data collection.

WHO Simplified Methodology (1987) is being applied in several studies: the Task Force on Methods for the Natural Regulation of Fertility of the Special Program on Human Reproduction in centers in Chendu, China; Guatemala City, Guatemala; New Delhi, India; Sagamu, Nigeria; Santiago, Chile; Uppsala, Sweden; and Westmead/Sydney, Australia. 550 lactating mothers who can read and write were examined in order to provide a better understanding of the relationship between breast-feeding duration and lactational amenorrhea, and to determine whether the longitudinal study results are applicable to the general population. Protocol involved data collection of breast-feeding frequency, timing, and duration; supplementary feeding characteristics and timing; and maternal and infant health. WHO protocol is also being examined in studies in Colombo, Sri Lanka, and Sagamu, Nigeria. The study objective was to examine the effect of maternal nutritional supplementation with skimmed milk powder in Colombo and a high protein biscuit in Sagamu on the duration of lactational amenorrhea in moderately malnourished breast-feeding mothers. Followup studies are expected. Optimally, the end product should be a measure of the presence of ovulation, however, the logistics prevented this from occurring. Instead, weekly urine samples were collected and tested for the presence of estrogen and pregnanediol glucuronide. Motivation is a key determinant in the success of these projects, since detailed record keeping over a prolonged period of time is required. Motivational interventions vary between centers and may involve social contact with investigators or health care support for the mother and infant. Some preliminary results indicate that the higher the percentage receiving supplementation, the earlier the return of the menses.     

Contraception after childbirth in Thailand

Data from the Third Contraceptive Prevalence Study conducted in 1984 in Thailand were analyzed to learn the extent of contraceptive practice after childbirth. Focusing on those women who had a birth within a given period prior to the survey, for some purposes the analysis was limited to those women whose most recent birth occurred within 1 year of interview, while for others it was extended to women whose most recent birth occurred within the last 2-4 years. The number of women in 4 years following childbirth in the Contraceptive Prevalence Survey 3 sample were 3442 in the unweighted ever married group and 3342 in the unweighted currently married group; the figures were 3447 for the weighted ever married group and 3342 for the weighted currently married group. Thai couples adopted contraception in very substantial proportions and very soon following the birth of a child. Based on women interviewed within 1 year of most recent birth, over half started some contraception by the end of the 6th month and almost 4/5 by the end of the 1st year. The timing of female sterilization was quite different from initiation of all other methods. Female sterilization in Thailand occurred primarily during the immediate postpartum period, while women are still in the hospital after delivery. Relatively few women sterilized in the 2 years following the 1st postpartum month. Of women in their first 2 years following childbirth, 17% were sterilized by the end of the 1st postpartum month and only an additional 3% by the end of the 2nd year. Initiation of temporary methods was not linked to the immediate postpartum period but occurred throughout the 1st year following birth. Contraceptive use during the 1st year following childbirth was more likely among menstruating women than among women who were still amenorrheic. Methods other than female sterilization predominated among women who already experienced the return of menses, suggesting that the return of menses was an important stimulus to their adoption. The data suggest that the proportion of Thai women exposed to risk of unwanted pregnancies for any extended period of time following childbirth is quite modest.     

Nursing does affect the duration of the post-partum to ovulation interval in cotton-top tamarins (Saguinus oedipus)

Reports on callitrichid monkeys have not revealed a significant effect of nursing on interbirth intervals or on post-partum to ovulation intervals. We examined 25 post-partum intervals in cotton-top tamarin females to determine whether nursing infants would affect the length of the post-partum to ovulation interval. Urinary LH/CG and oestrone conjugates were measured in urine samples collected in the 6 weeks after birth. The post-partum to ovulation interval is the number of days between parturition and the rise of urinary LH and oestrone conjugates associated with ovulation. There was an 84% conception rate post partum. Neither mother's parity nor sex of the infants influenced the length of the post-partum to ovulation interval. The post-partum to ovulation interval for females nursing 2 infants was twice as long as for those not nursing or nursing 1 infant (P less than 0.05). The range of post-partum to ovulation interval lengths was more variable in nursing than in non-nursing females (P less than 0.01). Females spent less than 50% of observed time in contact and less than 20% of observed time nursing their infants. Neither the number of tamarins within the family nor the amount of time the mother was in contact with infants correlated with the length of the post-partum to ovulation interval. However, there was a positive correlation between the percentage time that mothers nursed 1 infant at a time and the length of the post-partum to ovulation interval (r = 0.75, P less than 0.02). The underlying mechanisms of suckling-induced delay of ovulation are present in the cotton-top tamarin as in other primate species. However, these nursing effects do not cause the substantial delay in fertility post partum that is associated with non-callitrichid primates.     

The recovery of ovarian function during breast-feeding

The pattern of breast-feeding was daily recorded and the serum concentrations of prolactin (PRL), FSH, LH, estradiol (E2) and progesterone (prog) were measured at weekly intervals in 26 breast-feeding mothers from the time of delivery and up to the resumption of regular ovulation or to the end of the first postpartum year. Twelve postpartum non-breast-feeding women were similarly studied as controls. An algorithm was used to characterize ovulatory events into three types: the first, with evidence highly suggestive of normal ovulation (EHSO), the second, with evidence of probable ovulation (EPO) and the third with evidence indicating questionable ovulation or deficient corpus luteum function (QO/DCT). Pregnancy preceded the first menstruation in one woman in each of the breast-feeding and control groups. Of the 19 breast-feeding women who started to menstruate during the first postpartum year, five had EHSO, one had EPO, 5 had EQO/DCL and 7 had anovulatory (AO) menstruation. The corresponding figures in the 11 controls were 6, 2, 3 and 0. Pregnancy occurred before a second menstruation in one woman in both the study group and the controls. In 18 breast-feeding women observed, the second menstruation was preceded by EHSO in 7, by EPO in 3, by EQO/DCL in one and AO in 7. In 10 controls the corresponding figures were 7, 3, 0 and 0. Out of a total of 79 menstruations observed during breast-feeding the incidence of AO was 30% and of QO/DCL was 15%. In actively breast-feeding mothers, hyperprolactinemia persisted for more than 1 yr. However, menstruation and ovulation occasionally occurred before the drop of PRL to concentrations seen during the normal menstrual cycle. In the majority of women, low E2 levels were present during lactational amenorrhea, but with occasional spikes in some. A few women maintained somewhat high values of E2 for several weeks before the resumption of menstruation. The implications of these hormonal findings to the attempts to improve on the contraceptive effect of breast-feeding are discussed.     

Continuously recorded suckling behaviour and its effect on lactational amenorrhoea.

The hypothesis that the month-specific rate of return to ovarian cyclicity after childbirth is causally related to suckling pattern was tested for a population of New Mexican women recruited within the service area of New Mexico Highlands University and for a nationwide USA subpopulation of women recruited through membership of the Couple to Couple League (CCL). Survival analysis for time-dependent covariates was used, and significant predictors of the first postpartum menses were found. Important differences were detected in the suckling pattern for the two groups and a 5:2 differential was found in their respective rates of menstrual cycle recovery. Although the two groups were comparable perinatally, daily and time-windowed breast-feeding performance fell off at twice the rate for the New Mexico population when contrasted with the CCL sample. For both populations, the introduction of solid feeds was a strong and significant predictor of returning menstrual cyclicity, independent of suckling pattern.     

Post-partum events and fertility control in Kinshasa, Za?re

Contraceptive prevalence surveys from sub-Saharan Africa typically show low rates of method use. The current study of one zone in Kinshasa, Za?re, provides a more detailed view of fertility control in an urban population by examining the relative duration of breast-feeding, amenorrhoea and sexual abstinence during the post-partum period. While motivations to prevent pregnancy remain high until the youngest child is over 24 months, the average duration of abstinence is only 4 months. This paper describes the methods women use to avoid pregnancy and the changes over the post-partum period.     

Breast feeding and risk of breast cancer in young women. United Kingdom National Case-Control Study Group.

OBJECTIVE--To investigate whether breast feeding is related to subsequent risk of breast cancer. DESIGN--Population based case-control study designed primarily to investigate the relation between oral contraceptives and risk of breast cancer; data obtained from questionnaires administered by interviewers, general practitioner notes, and family planning clinic records. SETTING--11 health regions in Britain. SUBJECTS--Women diagnosed with breast cancer before age 36 living in the defined study areas. One control per case, matched for age, was selected from the list of the case''s general practitioner. 755 case-control pairs were interviewed. MAIN OUTCOME MEASURES--Duration of breast feeding each liveborn infant; timing of return of menses; hormone use; other risk factors for breast cancer. RESULTS--Risk of breast cancer fell with increasing duration of breast feeding (relative risk = 0.94 per three months'' breast feeding; test for trend p = 0.026) and with number of babies breast fed (relative risk = 0.86; test for trend, p = 0.017). Breast feeding each baby for longer than three months conferred no additional benefit. Breast feeding was more strongly negatively associated with risk of breast cancer than duration of postpartum amenorrhoea (chi 2 test for trend, p = 0.69). Hormonal suppression of lactation was unrelated to risk of breast cancer (relative risk = 0.96 per episode of suppressed lactation; test for trend, p = 0.72). CONCLUSIONS--These results suggest that breast feeding protects against the development of breast cancer in young women.     

Determinants of breast-feeding and post-partum amenorrhoea in Orissa

A life table analysis is made of the duration of breast-feeding and post-partum amenorrhoea in Orissa, India, taking one variable at a time using data from a baseline survey of fertility and mortality (BSFM) conducted on the lines of the World Fertility Survey. Then a multivariate (proportional hazard) analysis showed that socioeconomic factors including residence, caste status and education influence the breast-feeding and post-partum amenorrhoea periods. There was no effect of maternal age on the length of breast-feeding, but mean length of post-partum amenorrhoea varied with age. The durations of breast-feeding and post-partum amenorrhoea are strongly related.     

Gender differences in psychotic bipolar mania

Objective: This study examined gender differences in the prevalence and types of psychotic symptoms in bipolar mania.Methods: Participants were drawn from consecutive admissions to the psychiatric clinic in Chemnitz, Germany, in 2005. The diagnosis of bipolar disorder, manic episode was made within 24 hours of admission, and the severity of mania was assessed using the Young Mania Rating Scale (YMRS) and the German version of the Altman Self-Rating Mania Scale. Data collected for each patient included age at the onset of bipolar illness, number of previous episodes, social functioning between episodes, and duration of hospitalization for the index episode. Based on the Task Force for Methods and Documentation in Psychiatry system, psychotic symptoms were classified as hallucinations (visual, auditory, olfactory, tactile, acousma, somatic); delusions (paranoid, reference, guilt, grandeur, religious, erotomania, hypochondriac, poverty, jealousy); and ego disorder (thought control, thought broadcasting).Results: One hundred thirty-seven women and 109 men met the criteria for an acute manic episode, of whom 93 women and 62 men had psychotic symptoms. Compared with psychotic men, psychotic women had more delusions and hallucinations, both overall and per patient, and more delusions of reference and paranoid delusions. Psychotic women had more mixed states compared with psychotic men. Psychotic women differed from both psychotic men and nonpsychotic women on a number of clinical and social variables: they had higher YMRS scores and more previous episodes of depression despite an earlier onset of illness.Conclusion: Women with bipolar mania exhibited a specific pattern of psychotic symptoms that appeared to be associated with greater severity of the acute episode, more mixed states, and a more severe course of illness.