Sexual orientation, handedness, sex ratio and fetomaternal tolerance-rejection

Fraternal birth order (FBO) appears as a prenatal cause of 15% of homosexual males (gays) through mnemonic maternal anti-male factors. Non-right-handed men seem to be protected from homosexuality. Four hypotheses are proposed: (1) androgenic factors of non-right-handedness neutralize anti-male factors; (2) non-right-handedness and homosexuality are lethal or produce mental impairment; (3) non-right-handed male embryos are insensitive to anti-male factors; (4) mothers of non-right-handed fetuses do not produce anti-male factors. Studies of the sex ratio (SR) of older and younger siblings show: (1) a significant heterogeneity in the SR of siblings of right or non-right handed heterosexual men and women; (2) lesbians are born among siblings with high SR; (3) siblings of right-handed gays show a higher SR than non-right-handed gays that present a low SR. Based on our discovery of maternal tolerance-rejection processes, associated with genetic systems (ABO, Rh), where zygotes or embryos different from their mother induce better pregnancy and maternal tolerance than do those that share antigens with their mothers, I propose a new explanation for sexual relationships, sexual orientation, handedness and sibling SR. Lesbian embryos could induce tolerance from mothers with anti-female factors. Non-right-handedness could induce maternal tolerance, or change the maternal compatibility of "gay" embryos. Alternatively, gay embryos could be poor inducers of maternal tolerance towards male traits.     

Birth Timing and Behavioral Responsiveness Predict Individual Differences in the Mother–Infant Relationship and Infant Behavior During Weaning and Maternal Breeding

There is a great deal of variability in mother–infant interactions and infant behavior across the first year of life in rhesus monkeys. The current article has two specific aims: (1) to determine if birth timing predicts variability in the mother–infant relationship and infant behavior during weaning and maternal breeding, and (2) to identify predictors of infant behavior during a period of acute challenge, maternal breeding. Forty‐one mother–infant pairs were observed during weaning when infants were 4.5 months old, and 33 were followed through maternal breeding. Subjective ratings of 16 adjectives reflecting qualities of maternal attitude, mother–infant interactions, and infant attitude were factor analyzed to construct factors relating to the mother–infant relationship (Relaxed and Aggressive) and infant behavior (Positive Engagement and Distress). During weaning, late born infants were more Positively Engaged than peak born infants (ANOVA, P < 0.05); however, birth timing did not affect the mother–infant relationship factors Relaxed and Aggressive or the infant attitude factor Distress. During maternal breeding, early born infants had less Relaxed relationships with their mothers than peak or late born infants, higher Positive Engagement scores than peak or late born infants, and tended to have higher Distress scores than peak born infants (repeated‐measures ANOVA, P < 0.05). In addition, Distress scores were higher during maternal breeding than during the pre‐ and postbreeding phases. Finally, multiple regression (P < 0.05) indicated that while infant behavioral responsiveness predicted infant Positive Engagement during the acute challenge of maternal breeding, qualities of the mother–infant relationship predicted infant Distress. These data suggest that birth timing influences the patterns of mother–infant interactions during weaning and maternal breeding. Additionally, infant behavioral responsiveness and mother–infant relationship quality impact infant social engagement and affect expression, respectively. Am. J. Primatol. 74:734‐746, 2012. © 2012 Wiley Periodicals, Inc.     

Maternal Social Disadvantage and Newborn Telomere Length in Archived Dried Blood Spots from the Michigan Neonatal Biobank

Telomeres are the protective caps at the ends of eukaryotic chromosomes. Short telomere length is associated with morbidity and mortality among adults and may mark the biological impact of social experiences. Using archived dried blood spots from the Michigan Neonatal Biobank, this study examined markers of maternal social disadvantage (educational attainment, receipt of public assistance, marital status, and race/ethnicity) from linked birth certificates as predictors of telomere length at birth in a sample of 192 singleton neonates born to non-Hispanic black, non-Hispanic white, and Latina mothers aged 20–35 years. Consistent with two recent studies in newborns, but counter to the idea that maternal social disadvantage is associated with shorter offspring telomere length, we found that infants born to black mothers had longer telomeres than those born to white mothers (b = 0.12, SE = 0.06, p = .05). However, black/white differences in newborn telomere length varied by receipt of public assistance. Among newborns whose mothers received WIC and/or Medicaid, there were no significant black/white differences in telomere length (b = 0.09, SE = 0.08, p = .25). In contrast, among those whose mothers did not receive public assistance—just 6 out of 69 infants born to black mothers versus 41 out of 69 infants born to white mothers—we found that babies born to black mothers had longer telomere length than babies born to white mothers (b = 0.37, SE = 0.16, p = .03). The interaction between black race/ethnicity and receipt of public assistance did not reach the conventional threshold for statistical significance (b = ?0.22, SE = 0.15, p = .13), suggesting that this finding may be due to chance. No other markers of maternal social disadvantage were related to infant telomere length. Although replication of these results in a larger sample with more infants born to black mothers with relatively high socioeconomic status is needed, this study offers preliminary support for the hypothesis that race/ethnic differences in newborn telomere length depend on social context.     

Clinical Evaluation of Rh0(D) Immune Globulin (Human) in Canada

—During 1966, clinical trials were conducted in three Canadian centres to determine the safety and efficacy of Rh₀(D) immune globulin (human) in preventing isoimmunization by the Rh₀(D) antigen in Rh-negative women delivering ABO-compatible Rh-positive infants.The candidates were randomly divided into control and treated groups; the treated mothers received an intramuscular injection of 300 μg. of anti-Rh₀(D) within 72 hours of delivery. Follow-up antibody screening tests were conducted on the sera of all patients six to nine months post partum.Of the 175 control patients, 11 or 6.2% became actively immunized to the Rh antigen, whereas complete protection against maternal Rh immunization was observed in the 191 treated patients.     

Incidence of Maternal Rh Immunization by ABO Compatible and Incompatible Pregnancies

The incidence of maternal Rh immunization in Rh-negative women following a single ABO compatible Rh-positive pregnancy is about 17%. This incidence was determined by following Rh-negative women through two Rh-incompatible pregnancies and analysing their sera for anti-Rh at the time of delivery of their second observed pregnancy. Maternal Rh immunization occurs almost exclusively after delivery; however, antibodies may not be detectable in the absence of further antigenic stimulation.The incidence of maternal Rh immunization when maternal-foetal ABO incompatibility is also present is 9–13% and 17% for group O and non-group O women respectively. This study emphasizes the need to offer Rh-immune prophylaxis to Rh-negative women having Rh-positive infants whether or not ABO incompatibility exists between the mother and infant.     

Rare phenotypes of placental alkaline phosphatase an analysis of relationships with some neonatal and maternal variables

Summary Placental alkaline phosphatase (Pl) polymorphism is due to the occurrence of three common alleles and more than fifteen rare ones at an autosomal locus. The high number and frequency (about 2%) of rare Pl alleles represent a very special case among polymorphic enzymes. Since the Pl gene is also special in that it is active only during intrauterine life, the allelic diversity and its maintenance may be connected with intrauterine environment and with fetal development.This study embraced 502 consecutive newborn infants from the white population of European descent of New Haven (Connecticut). Analysis of the relationship between rare Pl phenotypes and the following variables was carried out: gestational length, birth weight, maternal age, birth order, sex, fetal and maternal AB0 and Rh phenotypes, feto-maternal AB0 and Rh compatibility status, and previous spontaneous abortions.The results indicate a negative association of Pl rate types with the 0 phenotype in the mother and with male sex of the infant.The present data suggest that interactions with sex and with the AB0 system during intrauterine life may contribute to the maintenance of allelic, diversity in Pl system.     

Maternal care and infant development in <Emphasis Type="Italic">Callimico goeldii</Emphasis> and <Emphasis Type="Italic">Callithrix jacchus</Emphasis>

Callimico goeldii gives birth to single offspring, whereas other callitrichids, including Callithrix jacchus, twin. This study compares maternal effort and infant development in C. goeldii and C. jacchus; it is the first study to look at nursing frequency. Infants were observed from birth for 7 weeks in two captive groups each of C. goeldii and C. jacchus. C. goeldii mothers physiologically invested the same or less than C. jacchus mothers. C. goeldii mothers gained the same amount of weight during pregnancy in absolute terms as did the smaller C. jacchus. This results in a smaller gain in proportion to maternal weight but an equivalent proportional gain on a per fetus basis. C. goeldii mothers nursed their infants less based on duration of nursing bouts compared with C. jacchus mothers. C. goeldii mothers transported their infants exclusively through the first 2 weeks of life, which is longer than C. jacchus mothers, who exclusively transported infants only during the first week of life. As maternal infant carriage declined, other group members transported offspring in both species. C. goeldii infants engaged in independent locomotive sequences later in development and tasted solid foods less frequently than C. jacchus infants when compared at equivalent ages. A single, opportunistic milk sample obtained from a C. goeldii mother when her infant was 48 days old indicates that C. goeldii milk contains gross energy from crude protein within the range of variation observed in Callithrix milk. Despite the similarities in milk quality and prenatal effort in individual fetuses, C. goeldii infants gain weight faster from 0 to 18 months than do C. jacchus infants. A reduction in litter size allows C. goeldii mothers to spend more time carrying their infant and to delay weaning, thereby allowing accelerated infant and juvenile growth rates compared with C. jacchus.     

Tactics of care for young infants by forest-living ruffed lemurs (Varecia variegata variegata): Ground nests,parking, and biparental guarding

Over a 4 month period, systematic and ad libitum observations were conducted on two adult female black-and-white ruffed lemurs (Varecia variegata variegata) and their infants in a 3.5 ha forest enclosure. The females were mother and daughter, members of a family group that had been semifree-ranging for 2 years and 3 months at the time of the births. One to two weeks before parturition, the females independently constructed nests, in which they kept their infants during the first few weeks following parturition. The older mother, cage-reared herself, prepared at least one nest. Her daughter, who has lived in the forest since late juvenescence, prepared at least four. Two to three weeks after parturition, the mothers moved their infants high into trees. During periods of maternal absence, the infants were often alone, and they rarely or never moved, vocalized, or groomed themselves. The mothers often kept their infants together after nests were no longer used. Each infant nursed freely from both lactating females. The infants were carried orally only by their mothers and were never transported by clinging to the pelage of any group members. Previously, researchers suggested that ruffed lemurs build nests for care of infants high up in trees. The present observations, however, suggest that two major modes of neonate care in Varecia exist: serial use of multiple ground nests and “parking” of infants high in trees. Advance preparation of several nest sites, relative lack of large predators, alternate maternal and paternal guarding of infants, infant immobility during absence of mother, and rapid infant development make this tactic of care for neonates plausible.     

Early agonistic experience and rank acquisition among free-ranging infant rhesus monkeys

Several aspects of agonistic experience are described for freeranging infant rhesus monkeys (Macaca mulatta)on Cayo Santiago. Even before infants are fully integrated with peers in rank dominance based on maternal ranks,infants of highranking mothers tend to be threatened less frequently by other members of the group and are less likely to be threatened by unfamiliar individuals than are infants of lowranking mothers. There is no evidence that fearful interactions between pairs of infants are related to their mother’s ranks before 22 weeks of age. However, an imperfect hierarchy can be constructed for infants between 27 and 30 weeks of age. At this age,infants of higherranking mothers are also more likely to receive protection when threatened than are infants of lowerranking mothers. When protected, their protectors are less likely to emit fearful gestures to the infants’ threatener. Close female relatives appear to play a large role in the protection of infants and may be more directly responsible for the differences described above than the mother, other relatives, or other highranking members of the group. It is suggested that more than one mechanism, including intervention by the mother and by close female relatives,may be important in rank acquisition among peers.     

Prevention of Rh Hemolytic Disease of the Newborn

Rh_o(D)-Immune Globulin was given to 322 Rh-negative women delivered of ABO-compatible, Rh-positive infants with no apparent failures to suppress Rh sensitization. In contrast, 32 of 305 mothers of a control group made Rh antibody during the six months following delivery. In subsequent pregnancies, 69 women administered RhoGAM had no evidence of isoimmunization after delivery while six of forty mothers of the control study produced anti-Rh. RhoGAM, given within 72 hours of delivery in the amounts employed, was effective for suppression of Rh immunization.     

Maternal nativity status and pregnancy outcome among U.S.‐born Filipinos

Abstract

Using 1979–87 Hawaii vital record data on single live births, this study compares by nativity status of the mother the maternal characteristics and pregnancy outcomes of resident Filipino women. Among ethnic minorities in the United States, the pregnancy outcomes of U.S.‐born mothers have been reported to compare unfavorably to their foreign‐born counterparts. In this study, unequivocally preferential pregnancy outcome indicators were not observed for foreign‐born women. Contrary to expectations, a significant, but modest, increase in the risk of preterm delivery was found for infants of Philippines‐born mothers, along with a less favorable mean birth weight and gestational age. As a growing minority population in the United States, the atypical determinants and patterns of pregnancy outcome in this population warrants further investigation.     

Behavioural development of howling monkey twins (Alouatta palliata) in Santa Rosa National Park,Costa Rica

Twins born to a young female howling monkey in Santa Rosa National Park, Costa Rica were observed during the first 96 days of their life. The comparison of their development to that of single infants and the comparison of the behaviour of the mother of the twins to that of mothers of single infants revealed few differences. However, qualitative observations suggests that high costs are associated with maternal care of infant twins. The mother had difficulty carrying both infants and was the only female observed to become sick during the study. Increased costs of lactation were not compensated for by an increase in foraging time. It would seem that howling monkey mothers possess a maternal care system which is capable of providing suitable care to twins. However, the costs on the mother of raising twins is suggested as a factor selecting for a litter size of one.     

Maternal–fetal transmission of SIV in macaques: Disseminated adenovirus infection in an offspring with congenital SIV infection

To develop a nonhuman primate model for maternal–fetal transmission of HIV infection, we have inoculated pregnant Macaca nemestrina with uncloned SIV_Mne. Three animals inoculated during the third trimester delivered healthy infants. One of the three infants, a male born 31 days after the mother was inoculated with SIV, became virus-positive but failed to produce SIV-specific antibody and died with overt simian immunodeficiency and disseminated adenovirus (SV20) infection at age six and one-half months. SIV and adenovirus antigen could be demonstrated by immunohistochemical methods in multiple organ systems.     

Maternal responses to dead and dying infants in wild troops of ring-tailed lemurs at the Berenty Reserve,Madagascar

We describe responses of seven mothers and other troop members to dead and dying infants in several troops of ring-tailed lemurs(Lemur catta) at the Berenty Reserve, Madagascar. In contrast to mothers in simian species, ring-tailed lemur mothers rarely carried their dying, immobile or dead infants. However, they sniffed, licked, and touched them even after they had died. While the dying infants were still peeping, their mothers remained near them, and 15 to 76 min after the infants ceased to peep, they were left by their mothers. Six of the seven mothers returned to their dead infants several times within the first few hours after they had left them. All seven mothers gave repeated calls, such as “mew” and “pyaa,” when they were separated from either their dead infants or other troop members or both. Thus, each mother exhibited some form of maternal behavior toward her dead infant for hours after its death. These results indicate that there may not be a great gap in terms of maternal affection between simian and prosimian mothers. We also discuss visuospatial memory ability in ring-tailed lemurs and the causes of the infants’ deaths.     

Frequencies of ABO, Rh and Kell phenotypes in couples from Han, Kazak, Uyghur and Hui in Xinjiang: an inheritance simulation model for blood group incompatibility in new-born

The Xinjiang region with residents from more than 13 minorities represents an area of many diverse ethnicities. This ethnic diversity in relation to their blood groups and immune status may have a consequential impact on the clinical status of married couples. To evaluate the risks of haemolytic disease in new-born infants, we investigated the rate of blood-group incompatibility among 487 married couples from four ethnic minorities, namely the Han, Hui, Uyghur and Kazak populations. Han minority married couples showed significantly different ABO, Rh and K phenotype frequencies between marrial relationship, whereas there was no significant difference in ABO, Rh and K phenotypes between the Uyghur, Hui and Kazak .There was a significant difference between ABO blood types in Han married couples, in the Kazak Rh-C phenotype and in the Uyghur Rh-D phenotype. The Hui married couples only demonstrated ABO, Rh and K phenotypes. The Hui minority showed the highest incompatibility rate for Rh-C and Rh-E phenotypes between mothers and their new-born infants. The highest incompatibility rate for the ABO phenotype occurred in the Kazak group. These results particularly demonstrate the clinical issues relating to ABO and Rh incompatibility, in the Kazak and Hui minorities, respectively.     

The roles of DNA methylation of NR3C1 and 11β-HSD2 and exposure to maternal mood disorder in utero on newborn neurobehavior

Exposure to maternal mood disorder in utero may program infant neurobehavior via DNA methylation of the glucocorticoid receptor (NR3C1) and 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD-2), two placental genes that have been implicated in perturbations of the hypothalamic pituitary adrenocortical (HPA) axis. We tested the relations among prenatal exposure to maternal depression or anxiety, methylation of exon 1F of NR3C1 and 11β-HSD-2, and newborn neurobehavior. Controlling for relevant covariates, infants whose mothers reported depression during pregnancy and showed greater methylation of placental NR3C1 CpG2 had poorer self-regulation, more hypotonia, and more lethargy than infants whose mothers did not report depression. On the other hand, infants whose mothers reported anxiety during pregnancy and showed greater methylation of placental 11β-HSD-2 CpG4 were more hypotonic compared with infants of mothers who did not report anxiety during pregnancy. Our results support the fetal programming hypothesis and suggest that fetal adjustments to cues from the intrauterine environment, in this case an environment that could be characterized by increased exposure to maternal cortisol, may lead to poor neurodevelopmental outcomes.     

Early infant development and maternal care in free-ranging vervet monkeys

The interactions of infant vervet monkeys (Cercopithecus aethiops) with their mothers were examined during the first 12 weeks of life. During this period there was a gradual rise in behaviour associated with increasing independence from the mother: female infants were slightly advanced over males on measures of decreasing contact with mothers and increasing rejections from the nipple. There were differences between the mothers in the ways they interacted with their infants such that no consistent maternal styles could be defined. Dominance rank of the mother did however influence her behaviour towards her infant, and high ranking mothers tended to be less rejecting towards sons, but more rejecting towards daughters, than were low ranking mothers. It is suggested that since vervet mothers have access to allomothers they may not be limited to dichotomous mothering styles.     

Can Marmoset Mothers Count to Three? Effect of Litter Size on Mother–Infant Interactions

Harper (Parental Care in Mammals, Plenum Press, New York, 1981, p. 158) proposed that ‘there may be lower and upper limits for frequency or intensity of offspring stimulation that, on average, serve as reliable boundaries, below or above which it would be uneconomical to invest at all or at current levels.‘ This proposition was tested in captive common marmosets by comparing the responses of marmoset mothers exposed to differing number of infants. Fifteen common marmoset (Callithrix jacchus) litters (seven twin and eight triplet litters) from 11 different dams were observed for 6–12, 30‐min sessions over days 1–4 following birth. Mothers nursed smaller infants less frequently (F = 4.208, df = 1, 22; p = 0.052) regardless of litter size. The percent time mothers spent transporting (nursing and carrying) each infant was less for triplets than twins (F = 11.785, df = 1, 12; p = 0.005). Average transport bout length was significantly shorter for smaller infants (F = 7.566, df = 1, 22; p = 0.012) and was half as long for triplet infants as for twins (F = 10.733, df = 1, 7; p = 0.013). Twice as many transport bouts for triplets included maternal harassment of infants, than for twins (F = 42.742, df = 1, 24; p = 0.0001). Infant‐initiated transfers to the mother were more common for triplets than for twins (Mann–Whitney U = 79.50, p = 0.006). The overall maternal carrying score (% carry × number of infants carried) was lower for triplet litters than for twin litters (F = 15.38, df = 1, 3; p = 0.029); i.e. mothers of triplets did not, overall, invest in more carrying and nursing than did mothers of twins but instead invested less. These findings suggest that, as opposed to the strong attraction to infants that is common for many primates, the marmoset mother's tolerance for carrying infants does not increase with increasing infant stimuli present; rather, marmoset mothers will only tolerate a limited amount of time transporting and nursing infants, regardless of litter size. This limited tolerance may be due to the species’ small body size and anti‐predator strategies (e.g. concealment) that make infant care incompatible with other essential activities, such as foraging.     

Effect of ABO Incompatibility on Pregnancy-Induced Rh Isoimmunization

The protective effect of ABO incompatibility between mother and fetus in respect of pregnancy-induced Rh isoimmunization has been recognized for approximately 20 years. Many have tacitly assumed that this protection was absolute and that when an infant was born with Rh hemolytic disease of the newborn, who was also ABO-incompatible with its mother, there must have been a previous ABO-compatible pregnancy in which the mother was initially sensitized. It has also been assumed that pregnancy-induced Rh isoimmunization could not occur if the father was AB and the mother O. Data are presented to show that both of these assumptions are not universally true. In a detailed study of a large number of families with pregnancy-induced Rh iso-immunization, nine families were found in which sensitization occurred and in which ABO incompatibility was present in every pregnancy. In addition, three families are documented in which pregnancy-induced Rh immunization had occurred and in which the father was AB and the mother O.     

Patterns of low birth weight in the Bengali newborns

This paper examines the distribution of low birth weight (2500 g or less) by gestation time, sex, maternal age, parity (birth order), socioeconomic conditions, and season of birth among 5117 single live births born to Bengali mothers at the Ramakrishna Mission Seva Pratisthan Hospital in Calcutta, India. Preterm infants have low birth weight significantly more often than their full term counterparts. Female infants have low birth weights significantly more often than male infants. The infants of poor mothers have lower birth weights in higher order births more often than infants of higher orders born to well-off mothers. Teenaged mothers produce low birth weight babies significantly more often than older mothers. Although the relationship is not significant, low birth weight infants occur more often among 1st and late born infants and less often among 2nd born infants. The season of birth is not significantly associated with birth weight. Less than 10% of low birth weight infants are pre-term, while the rest are full term. The great majority of low birth weight infants are small-for-gestational-age; the minority are small due to curtailed gestational age. The proportion of infants weighing less than 2001 g is only 9%; this figure tallies closely with earlier studies of India.