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If you had been sexually active around ovulation time, you can expect chances of pregnancy (provided there are no other factors affecting your fertility level). If you suspect to be pregnant, look out for development of any new symptoms suggestive of pregnancy, or signs like missing your periods. Beta HCG can be detected in maternal plasma or urine by 8 to 9 days after ovulation, by a blood test about 11 days after conception, and about 14-18 days after conception by a urine test. Usually the HCG levels will double every 72 hours if the pregnancy is going on smoothly. Urine pregnancy test kits usually start showing positive results after about 20 days post-conception (roughly corresponding to about 1 week after your missed/altered periods). The test should always be done on early morning first urine sample to get accurate results (pregnancy hormone HCG is believed to be in highest concentration in this sample, and you should avoid lot of fluid intake and caffeinated beverages in the night before taking the test). If you suspect being pregnant, but have been getting negative urine pregnancy results, you should consider visiting your doctor/gynecologist at the earliest for thorough examination (to confirm pregnancy related changes/signs in body) and blood/serum HCG level test (to confirm/rule out pregnancy accurately). Be in regular monitoring and follow-up with your treating doctor/gynecologist and report any new/abnormal symptoms immediately.
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