First‐Trimester Prognosis When an Early Gestational Sac is Seen on Ultrasound Imaging

Abstract

Objectives To determine the factors that jointly and independently affect first‐trimester outcome of very early intrauterine pregnancies (those whose sonogram shows a gestational sac with no identifiable yolk sac or embryo) and develop a mathematical model and Web‐based calculator that computes prognosis based on these factors. Methods Our study population included 590 very early pregnancies scanned between January 1, 2012, and June 30, 2018, with known outcomes (live or spontaneous loss) at 14 weeks. We recorded patient age, mean sac diameter (MSD), human chorionic gonadotropin (hCG) rise, and presence/absence of: vaginal bleeding, history of infertility, prior miscarriage, and pregnancy via assisted reproductive technology. We assessed the correlation between each of these factors and outcome and performed stepwise logistic regression to determine the subset that independently correlated with outcome. Results Patient age, MSD, hCG rise, vaginal bleeding, history of infertility, and assisted reproductive technology pregnancy were significantly correlated with outcome (P < .05, t test for age and MSD, χ2 for the others). Stepwise logistic regression identified age, MSD, hCG rise, and vaginal bleeding as the subset of factors that independently predicted outcome. The regression model's area under the receiver operating characteristic curve was 0.823. We incorporated the regression model into a Web‐based calculator (https://tinyurl.com/Prognosis-PD) that predicts the outcome of an early intrauterine pregnancy based on these 4 key variables. Conclusions The prognosis of very early intrauterine pregnancies is related to several clinical, biochemical, and sonographic factors. The factors that independently correlate with first‐trimester outcome are patient age, MSD, hCG rise, and vaginal bleeding. The logistic regression model predicts outcome based on these variables.

Ectopic pregnancy: a resident’s guide to imaging findings and diagnostic pitfalls

“…An intrauterine gestational sac (GS) can typically be detected on TVUS once the serum beta-hCG exceeds 2000 mIU/mL [2]. This usually occurs 5 weeks following the patient's first day of prior menses or 3 weeks following conception [5,6]. The absence of an intrauterine pregnancy (IUP) with beta-hCG levels over 2000 mIU/mL should automatically prompt a thorough search for an EP, which may not always be visible.…”

Fourfold Improved Odds of a Good First Trimester Outcome Once a Yolk Sac Is Seen in Early Pregnancy

“…We have previously studied the prognosis of pregnancies with a transvaginal sonogram demonstrating a gestational sac with no identifiable yolk sac or embryo. 14 The current study extends the prior one by including pregnancies with a yolk sac but no embryo, focusing on the improved prognosis when a yolk sac is present. We found that the likelihood of a live first trimester outcome is significantly higher when a yolk sac is present, with the odds of a live outcome 4-fold higher than in pregnancies with a gestational sac containing no yolk sac.…”

“…We have previously studied the probability of a successful first trimester outcome in a pregnant woman whose sonogram demonstrates an intrauterine gestational sac without visible contents 14 . In that study, we examined prognosis without and with risk factors such as advanced maternal age and vaginal bleeding, and we developed a formula for assessing pregnancy outcome.…”

“…We have previously studied the probability of a successful first trimester outcome in a pregnant woman whose sonogram demonstrates an intrauterine gestational sac without visible contents. 14 In that study, we examined prognosis without and with risk factors such as advanced maternal age and vaginal bleeding, and we developed a formula for assessing pregnancy outcome. Our current study extends that investigation to include sonograms demonstrating a gestational sac with yolk sac but no identifiable embryo, in addition to those with a gestational sac with no visible contents.…”

Methodological Issues in the Development of a Prediction Tool for First‐Trimester Outcomes

“…To the Editor: Doubilet and colleagues 1 have presented a Web-based calculator to predict the firsttrimester outcome when a very early gestational sac (intrauterine saclike structures without a yolk sac or embryo) is seen on ultrasound imaging. Although an accurate prognostic tool for the first-trimester prognosis could be useful, we would caution against the use of this calculator for the following main reasons.…”