1. Pregnancy Outcomes Abortion More likely with multiple fetuses USG: two GSs with the subsequent disappearance of one or even both sacs is evidence that silent early abortion or resorption of one embryo is fairly common.

2. Death of one fetus At delivery : death fetusfetuscompressus & fetus papyraceous. Death fetus  mother coagulation defects. The placenta is the site of massive deposition of fibrin leads to decreasing of maternal fibrinogen and increasing of the FDP  heparin infusion. The risk of the living fetus to had consumptive coagulopathy  if there’s anastomose between fetal circulations.

3. Perinatal Mortality Higher than single fetus (10-15%). Monozygotic twins compared with dizygotic twins had higher chance (2.5x) to have monoamniotic sac or intertwining of umbilical cords. Duration of gestation Depends on the number of fetuses.

4. Birthweight Powers: 45-65% of twin infants had BW < 2.501g. Number of fetuses ↑, BW ↓. When two or more fetuses are derived from a single ovum, the degree of GR is likely to be greater than from different ovum. Two monozygotic infants  BW nearly the same. Dizygotic twins  marked discordance in size.

5. Malformations Kohl & Casey: twice as great in twins as in singletons. Malformations are more common among monozygotic. Persistent or chronic hydramnios associated with fetal anomalies of one or both. Hashimoto et al : increased amniotic fluid in a fourth of twin pregnancies (9 over 10 pregnancies).

6. Subsequent Development General intelligence did not appear to differ between twins & singleton. Height, weight, HC and apparently intellience often remain superior in the twin who weighted more at birth.

7. Superfetation & Superfecundation Superfetation: fertilizations happened with an interval as long as or longer than an ovulatory cycle. Superfecundation: fertiolizations happened within a short period of time but not at the same coitus, nor necessarily by sperm from the same man (or ejaculate).

8. Maternal Adaptation Greater maternal physiological change. Veille& associates : Cardiac output was increased, but end-diastolic ventricular dimensions were the same. In pregnancies with multiple fetuses  hydramnios  obstructive uropathy  impaired maternal renal function.

9. Management of Pregnancies Diet Increasing daily requirements Energy consumption ↑ 300kcal/day. Iron Supplementation : 60-100 mg/day. Folic Acid : 1 mg/day.

10. Maternal Hypertension Pregnancy-induced & pregnancy-aggravated hypertensions are much more likely to develop.

11. Prevention of Preterm Delivery Bed rest. Progestin administration Pulmonary Maturation Prolonged Gestation