sextuplet, newborn, nulliparous, monozygotic, infant, newborn baby, fraternal twin, dizygotic, pregnant, parous, cesarean section, cesarian section, conjoined twin, prepubertal, imperforate anus, cesarian, pyloric stenosis, intrauterine, maternal, newborn infant, gestational, giraffa camelopardalis, estrous cycle, amniotic cavity, bactrian camel, anencephalic, twin, neonatal, utero, caesarean section, atlantic bottlenose dolphin, unweaned, rh incompatibility, preterm, malayan tapir, conjoined, western lowland gorilla, unfed, littermate, nonpregnant, calfs, precocial, rhesus, stillborn infant, gestational age, anovulatory, malnourished, dwarf sperm whale, respiratory distress syndrome, caesarian, addax, neonatal mortality, pubertal, unhatched, puerperal, diaphragmatic hernia, antepartum, breech birth, congenital abnormality, molar pregnancy, parthenogenetic, preterm infant, pygmy marmoset, identical twin, in vitro, baby talk, eldest, hyperemesis gravidarum, caesarean delivery, emaciated, stillborn, furless, rhesus monkey, colicky, breech presentation, orphaned, subadult, lactalbumin, placenta previa, sloth bear, neural tube, giant anteater, neuromotor, polyandrous, biological, fetal distress, teenaged, towheaded, proband, postnatal, chromosomal anomaly, siamese, blastocyst, zygotic, surrogate mother, monozygotic twin, congenital disorder, adoptive, colobus monkey, undernourished, hmg, singleton, nonviable, triplet, fullterm, postmature, postterm, primiparous, uncomplicated, unwed, age, anisotropic, antisymmetric, base, bimolecular

digit, set, sib, sibling

4, four, foursome, iv, little joe, quad, quartet, quartette, quatern, quaternary, quaternion, quaternity, tetrad