Metode Shettles
Dr. Landrum Shettles proposed that Y-sperm (male) are faster but shorter-lived, while X-sperm (female) are slower but more resilient.
- Untuk Laki-laki: Dekat ovulasi.
- Untuk Perempuan: 2-4 hari sebelumnya.
Metode Shettles.
Dr. Landrum Shettles proposed that Y-sperm (male) are faster but shorter-lived, while X-sperm (female) are slower but more resilient.