Our study aims to describe the effect of the intrauterine adminstration of HCG versus the endometrial injury by pipelle on the ongoing pregnancy rate and the biochemical pregnancy rate in women with unexplained infertility undergoing ovulation induction. Also to describe the effect on the first trimester miscarriage rate, ectopic pregnancy rate, and multiple pregnancy.This study is an open-label, prospective, controlled study, multi-center study.

The study participants' relevant medical records will be collected and reviewed after obtaining informed consent for the participants. The study materials that will be used will include blood tests, and ultrasound. The study will involve three study arms.

Our study aims to describe the effect of the intrauterine adminstration of HCG versus the endometrial injury by pipelle on the ongoing pregnancy rate and the biochemical pregnancy rate in women with unexplained infertility undergoing ovulation induction. Also to describe the effect on the first trimester miscarriage rate, ectopic pregnancy rate, and multiple pregnancy.This study is an open-label, prospective, controlled study, multi-center study.

The study participants' relevant medical records will be collected and reviewed after obtaining informed consent for the participants. The study materials that will be used will include blood tests, and ultrasound. The study will involve three study arms:

Arm 1: Women with unexplained infertility undergoing ovulation induction following intrauterine adminstration of HCG on the day of trigger Arm 2: Women with unexplained infertility undergoing ovulation induction following endometrial injury by pipelle on day 8-9 of the same cycle of ovulation induction Arm 3: Women with unexplained infertility undergoing ovulation induction following intrauterine adminstration of placebo on the day of trigger

Primary and secondary key measurements will be used in the study.

The primary measures will include:

• Signs of ongoing pregnancy Presence of intrauterine gestational sac at 12 weeks Presence of fetal heart pulsation at 12 weeks
• Two serum β-HCG levels in 48hrs interval to emphasis biochemical pregnancy

The secondary key measures will include:

• Occurance of abortion in the 1st trimester
• Appearance of ectopic pregnancy diagnosis by:

Ultrasound Serum β-HCG level Symptoms of pain and bleeding

• Signs of multiple pregnancy Number of intrauterine gestational sacs Number of fetal poles Number of fetal heart pulsations
• Recording the the baseline characteristics of the study participants

Inclusion Criteria:

1. Women with primary or secondary infertility due to unexplained infertility
2. The age group of these women was 25-35 years
3. BMI 18.5-29.9 kg/m2
4. Normal hormone profile (FSH <10 mIU/ml on day 2-3 and AMH more than 1)
5. Euthyroid state or controlled thyroid state
6. Bilateral free spill on HSG

Exclusion Criteria:

1. Patients with severe male factor infertility; serum analysis count < 10 million sperms /mL - sperm motility<15% - 96%\

The study population will include women with unexplained infertility undergoing ovulation induction following either:

1. Intrauterine adminstration of HCG
2. Endometrial injury by pipelle
3. Intrauterine adminstration of placebo