Sonogram dating and birthdate
However, many differences in each woman’s cycle may hinder the accuracy of the conception date calculation.
The viability of sperm varies as well, which means intercourse three to five days prior to ovulation may result in conception.
The long-term effects of repeated ultrasound exposures on the fetus are not fully known.
It is recommended that ultrasound only be used if medically indicated. The heartbeat may not be detected for reasons that include: tipped uterus, larger abdomen, or inaccurate dating with last menstrual period.
If there are any questions regarding gestational age, placenta location, or possible complications then more ultrasounds may be scheduled.
Your healthcare provider will use hormone levels in your blood, the date of your last menstrual period and, in some cases, results from an ultrasound to generate an expected date of conception.
There are basically seven different ultrasound exams, but the basic process is the same.
The different types of procedures include: Transvaginal Scans – Specially designed probe transducers are used inside the vagina to generate sonogram images.
Your healthcare provider uses a transducer to produce sound waves into the uterus.However, variations in each woman’s cycle and each pregnancy may hinder the accuracy of the gestational age calculation.If your healthcare provider uses an ultrasound to get an estimated delivery date to base the timing of your prenatal care, the original estimated gestational age will not be changed.Ultrasound dating of conception is not reliable for determining paternity because the ultrasound can be off by at least 5-7 days in early pregnancy.
You may have an ultrasound between 18 to 20 weeks to evaluate dates, a multiples pregnancy, placenta location or complications.
If you receive an ultrasound exam after week 6, your healthcare provider will begin to be concerned, if there is no gestational sac.