Most women with recurrent pregnancy losses tend to experience spontaneous abortion at approximately the same gestational age in sequential pregnancies (321). Unfortunately, the gestational age when pregnancy loss occurs, as determined by last menstrual period, may not be informative, because there is often a 2-to 3-week delay between fetal demise and signs of pregnancy expulsion (322). The designation of couples experiencing recurrent abortion into either primary or secondary categories is not helpful in either the diagnosis or management of most women with recurrent abortion. Approximately 10% to 15% of couples cannot be classified into either the primary or secondary category because, although their first pregnancy resulted in a loss, it was followed by a term delivery prior to subsequent losses.
It is important to glean any history of subfertility or infertility among couples with recurrent pregnancy loss. This is defined as the inability to conceive after 12 months of unprotected intercourse. By definition, 15% of all couples will meet this criteria; this number increases to 33% among couples with recurrent pregnancy losses. Because many pregnancies are lost before or near the time of missed menses, subfertility among recurrent pregnancy loss patients may in some cases reﬂect recurrent preclinical losses. Menstrual cycle history may provide information about the possibility of oligo-ovulation or other relevant endocrine abnormalities in recurrent pregnancy loss patients. An assessment of the timing of intercourse relative
Table 33.3 Investigative Measures Useful in the Evaluation of Recurrent Early Pregnancy Loss 1.
Pattern, trimester, and characteristics of prior pregnancy losses 2.
History of subfertility or infertility 3.
4.
5.
Signs or symptoms of thyroid, prolactin, glucose tolerance and hyperandrogenic disorders (including polycystic ovarian syndrome) 6.
7.
Features associated with the antiphospholipid syndrome (thrombosis, false positive test for syphilis) 8.
9.
10.
Environmental exposures, illicit and common drug use (particularly caffeine, alcohol, cigarettes, and in utero diethylstilbestrol exposure) 11.
12.
Family history of recurrent spontaneous abortion, of obstetric complications, or of any syndrome associated with embryonic or fetal losses 13.
Previous diagnostic tests and treatments, including, if available, chromosome testing on products of conception.
1. General physical examination with particular attention to: a.
b.
c.
d.
e.
1.
2.
3.
4.
5.
1.
2.
Chromosome testing on products of conception 3.
Hysterosalpingography, three-dimensional transvaginal sonography, sonohysterography, or office hysteroscopy, followed by hysteroscopy/laparoscopy, if indicated 4.
Thyroid stimulating hormone level, serum prolactin level if indicated 5.
6.
7.
8.
Complete blood count with platelets 9.
Factor V Leiden, G20210A prothrombin gene mutation, protein S activity, homocysteine level, activated protein C resistance (in white patients with suspicious family history) 10.
Protein C activity, antithrombin level if personal or family history of venous thromboembolic events to ovulation should be reviewed with couples in an effort to detect dyssynchronous fertilization that could contribute to pregnancy loss (323). A personal and family history of thrombotic events or renal abnormalities may provide vital information. A family history of pregnancy losses and obstetric complications should be addressed specifically. Detailed information about drug and environmental exposure should also be obtained.