Dating pregnancy with ultrasound
Daily immunoactive and bioactive human chorionic gonadotropin profiles in periimplantation urine samples. The American College of Obstetricians and Gynecologists. Timing of sexual intercourse in relation to ovulation.
Other Methods For Estimating the Gestational Age Clinical Examination A pelvic examination supported by good menstrual records in the first trimester has been reported to be a reliable method for dating of pregnancy .
The tendency for multiple gestations to be delivered earlier than singleton pregnancies should not be interpreted that multiples should be assigned an earlier estimated due date.
A full term pregnancy is considered to be 39 to 40 6/7 weeks regardless of the number fetuses being carried . Chervenak FA, Skupski DW, Romero R, et al: How accurate is fetal biometry in the assessment of fetal age?
Twins When a twin pregnancy is the result of in vitro fertilization determination of gestational age should be made from the date of embryo transfer. Clinical management guidelines for obstetricians-gynecologists. Number 55, September 2004 (replaces practice pattern number 6, October 1997).
Otherwise "..avoid missing a situation of early intrauterine growth restriction in one twin, most experts agree that the clinician may consider dating pregnancy using the larger fetus." [22,23].