Please consult your healthcare provider for any health related questions and issues. It is not accurate enough to be used for preventing pregnancy or any other purpose requiring accurate ovulation determination. Typically, fundal height measurements offer reassurance of a baby's steady growth. Disclaimer: This ovulation calculator is intended for educational purpose only. And further research is needed to determine how effective it is in detecting intrauterine growth restriction. Its accuracy depends on the mothers LMP first-day recall and cycle length.

Too much amniotic fluid (polyhydramnios)ĭepending on the circumstances, your health care provider might recommend an ultrasound to determine what's causing the unusual measurements or more closely monitor your pregnancy.īut fundal height is only a tool for gauging fetal growth - it's not an exact science. The LMP method assumes regular 28-day cycles and that ovulation and conception occur precisely on the 14th day of the cycle.Too little amniotic fluid (oligohydramnios).The implanting embryo has to somehow 'eat' its way into it, and a little bleeding may happen as a result. During implantation, the uterine lining is very thick, and filled with many twisted blood vessels.

A significantly larger than average baby (fetal macrosomia) We already calculated your implantation time, which is when the implantation bleeding may happen.Slow fetal growth (intrauterine growth restriction).For Caucasian women who were not first-time moms, their date of delivery averaged 283 days past LMP (three days after Naegele’s rule. A fundal height measurement might be less accurate, however, if you have a body mass index of 30 or higher (obesity) or have a history of fibroids.Ī fundal height that measures smaller or larger than expected - or increases more or less quickly than expected - could indicate: The Mittendorf-Williams rule is based on two studies: This study done in 1990 that showed pregnancy lasted an average of 288 days past a woman’s last menstrual period (LMP) for Caucasian first-time moms.

Accurate conception calculator